Improvement in low-water indicators



R. R. CARPENTER.

Low-water Indicators. `N0.1 57,n8. nfednom rrrrr Pat UNITED STATES RALPH R. CARPENTER, OF TIPPECANOE CITY, OHIO.

IMPROVEMENT IN LOW-WATER INDICATORS.

Specification forming part of Letters Patent No. 157,11 S, dated November 24, 1874; application liled November 2, 1874.

To all whom t may concern Be it known that I, RALPH R. CARPENTER, of Tippecanoe City, in the county of Miami and State of Ohio, have invented certain new and useful Improvements in Low-Water Indicators; and I do hereby declare that the following is a full, clear, and exact description thereof, referencebein g had to the accompanying drawings and to the letters of reference marked thereon, which form part of this speciication. Y

My invention relates to that class of lowwater alarms operated by the variable expansion of different kinds of metal; and it consists of a brass tube secured to the boiler, and carrying the whistle at its upper end, and a steel rod connected to the valve in the whistle, and passing longitudinally through the brass tube, so that the excess of expansion of the exterior tube over the interior rod will cause the valve to open, and give free passage to the steam to sound the alarm.

In order to enable others skilled in the art to which my invention appertains to make and use the same, I will now proceed to describe its construction and operation, referring to the annexed drawing, in which- Figure 1 is a side elevation, Fig. 2 is a central vertical section, Figs. 3, 4, and 5 are detailed views, of my invention.

A represents a brass tube, of suitable length, the lower end of which is provided with exterior screw-threads, to be screwed into the steam-boiler.

Ordinarily a coupling is permanently secured on the lower end of the tube A, and this coupling has the screw-threads to be inserted in the boiler. Either way will answer; but a shoulder, a, must be formed in any case within the lower end of the tube, around its inner circumference, as shown in' the drawing.

On the upper end of the tube A is permanently secured a cup, B, provided with interior screw-threads at its upper end, into which is screwed a valve-chamber, C, which contains a wing-valve, b, arrangedwith a spring, d, in such a manner as to close upward against the lower end of the valve-chamber. Ou the upper end of the valve-chamber C is screwed the ordinary whistle D, from the center of which extends the post f, and upon this post the bell E is attached. To the lower end of the valve b is attached a steel rod, h, which extends down through the center of the brass tube A, and has a cross-bar, i, screwed upon its lower end. The ends of this cross-bar should bear against the shoulder a in the interior of the lower end of the tube.

The principle involved in this alarm is the same as in all others where the variable expansion of different kinds of metal is made use of to sound the alarm. In this case the brass tube A will expand more than the steel rod h, and, as it expands, it raises the valvechamber or valve-seat C from the valve b, allowing the steam to pass to the whistle and sound the alarm. 'When water is admitted into the boiler the tube cools and contracts, bringing the seat down on the valve again.

By the construction and arrangement of the paris as described, the vvalve and Valverod being entirely within the single pipeA leading to the whistle, the device is rendered very simple and cheap, at the same time as it is durable, and there is nothing liable to get out of order.

The bell E is connected to the post f by means of screw-threads, so that the bell canthe bell is from the whistle D, it will take a' greater or less pressure of steam to sound the alarm when the valve is opened.

The valve b is adjusted by simply turning the valve-chamber C, and said chamber should first be gradually unscrewed until the valve will leak the least possible quantity, and then the valve-chamber is turned back, or screwed in, the merest triile. This will set the valve, so that a very small difference in the expansion of the standpipe an'l valver0d will cause the valve to open, admitting steam to sound the alarm.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In a steam-whistle alarm or low-water indicator, the expansive standpipe A, construeted at its upper end with cup B, and at I strueted and arranged to operate substanits lower end with an internal shoulder, a, in tiaily as and for thepurposes herein set forth. Combination with cross-bar z', rod h, and Valve In testimony that I claim the foregoing es b, substantially es and for the purpose set my oWu I efx my signature in presence of forth. two Witnesses.

2. The combination of the expansibie stand- RALPH R. CARPENTER. pipe A, Withvinterior shoulder a, and Valve- Witnesses: chamber B, Whistle D E, Valve b, With spring' T. H. ALEXANDER,

d, and valve-rod h, with cross-bar i, all cou- J. TYLER POWELL. 

